1. Field
One embodiment of the invention relates to an automatic operating system determination technique suitable for a personal computer on which a 32- or 64-bit operating system can run.
2. Description of the Related Art
In recent years, various types of personal computers such as notebook type computers and desktop type computers have prevailed. In such computers, an operating system (OS) manages the resources, and various application programs including utilities are executed under the control of the OS.
In this way, the OS plays an important role in the personal computer. Various techniques for dealing with the OS have been proposed (see, e.g., Jpn. Pat. Appln. KOKAI Publication No. 2-280229).
To manage the resources, the OS inquires of a Basic Input/Output System (BIOS) about the resources of the personal computer, i.e., the resources to be managed by the OS (a resource report). The OS then manages the resources on the basis of the contents of the resource report from the BIOS.
These days, a 64-bit OS which can use a memory area including more than 4 Gbytes has become more popular than a 32-bit OS which can use a memory area including at most 4 Gbytes. Along with this trend, the capacity of an expansion memory is increasing.
A user sets the OS running on the personal computer as a 32- or 64-bit OS by using, e.g., a utility program. The BIOS generally makes a resource report to the OS on the basis of the user setting. Assume that the user sets the OS as a 32-bit OS although it is a 64-bit OS. In this case, even if the capacity of the internal memory of the computer is much larger than 4 Gbytes, the BIOS sends, to the OS, a resource report representing a memory area with 4 Gbytes with which a 32-bit OS can deal.
To the contrary, assume that the user sets the OS as a 64-bit OS although it is a 32-bit OS. If the capacity of the internal memory of the computer is over 4 Gbytes, the BIOS sends, to the OS, a resource report representing a memory area with over 4 Gbytes with which a 32-bit OS cannot deal. This may cause a malfunction of the personal computer.
For this reason, there has been a strong demand for the BIOS to have a mechanism for automatically determining whether the OS running on the personal computer is a 32- or 64-bit OS.